fix: handle blank push notification config IDs (#1242)

* Fix blank push notification config ID handling

* test: exclude optional blank push config id

* ci: retrigger pull request checks

* fix: address push config ID review feedback

Author: prachisinghal-1

server-common/src/main/java/org/a2aproject/sdk/server/requesthandlers/DefaultRequestHandler.java

@@ -1210,7 +1210,6 @@ public TaskPushNotificationConfig onCreateTaskPushNotificationConfig(
     public TaskPushNotificationConfig onGetTaskPushNotificationConfig(
             GetTaskPushNotificationConfigParams params, ServerCallContext context) throws A2AError {
         validateRequiredId(context, "taskId", params.taskId());
-        validateRequiredId(context, "id", params.id());
         if (pushConfigStore == null) {
             throw new UnsupportedOperationError();
         }
@@ -1226,8 +1225,9 @@ public TaskPushNotificationConfig onGetTaskPushNotificationConfig(
         }
 
         String requestedConfigId = params.id();
-        String configId = Assert.isNullOrEmpty(requestedConfigId) ? params.taskId()
-                : Assert.checkNotNullParam("requestedConfigId", requestedConfigId);
+        String configId = requestedConfigId == null || requestedConfigId.isEmpty()
+            ? params.taskId()
+            : requestedConfigId;
         return getTaskPushNotificationConfig(listTaskPushNotificationConfigsResult, configId);
     }
 

server-common/src/test/java/org/a2aproject/sdk/server/requesthandlers/DefaultRequestHandlerBuilderAuthorizationTest.java

@@ -114,7 +114,6 @@ void tearDown() {
             "subscribe, ''", "subscribe, '   '",
             "createPush, ''", "createPush, '   '",
             "getPush, ''", "getPush, '   '",
-            "getPushId, ''", "getPushId, '   '",
             "listPush, ''", "listPush, '   '",
             "deletePush, ''", "deletePush, '   '",
             "deletePushId, ''", "deletePushId, '   '"

server-common/src/test/java/org/a2aproject/sdk/server/requesthandlers/DefaultRequestHandlerTest.java

@@ -81,6 +81,7 @@
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.CsvSource;
 import org.junit.jupiter.params.provider.NullAndEmptySource;
+import org.junit.jupiter.params.provider.ValueSource;
 
 /**
  * Integration tests for DefaultRequestHandler focusing on AUTH_REQUIRED workflow.
@@ -1262,6 +1263,29 @@ void testGetTaskPushNotificationConfigDefaultsMissingIdToTaskId() throws Excepti
         assertEquals("http://example.com/get-default-config-id", result.url());
     }
 
+    @ParameterizedTest
+    @NullAndEmptySource
+    void testGetTaskPushNotificationConfigDefaultsMissingIdToTaskIdWithEffectiveCard(String configId)
+            throws Exception {
+        String taskId = "get-default-config-id-with-card";
+        taskStore.save(Task.builder()
+                .id(taskId)
+                .contextId("ctx-get-default-config-id-with-card")
+                .status(new TaskStatus(TaskState.TASK_STATE_WORKING))
+                .build(), false);
+        requestHandler.onCreateTaskPushNotificationConfig(TaskPushNotificationConfig.builder()
+                .taskId(taskId)
+                .url("http://example.com/get-default-config-id-with-card")
+                .build(), NULL_CONTEXT);
+
+        TaskPushNotificationConfig result = requestHandler.onGetTaskPushNotificationConfig(
+            new GetTaskPushNotificationConfigParams(taskId, configId),
+            contextWithEffectiveCard(true));
+
+        assertEquals(taskId, result.id());
+        assertEquals("http://example.com/get-default-config-id-with-card", result.url());
+    }
+
     /**
      * Verify that onMessageSend stores the protocol version when the request
      * includes a push notification config (new task path).